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author | Andrii Nakryiko <andrii@kernel.org> | 2021-05-24 20:59:33 -0700 |
---|---|---|
committer | Alexei Starovoitov <ast@kernel.org> | 2021-05-25 17:32:35 -0700 |
commit | f12b654327283d158de0af170943ec5dd8cd02e5 (patch) | |
tree | 08eb76796d77a1f8b4d706ceb1059ebe59383d51 /tools/lib/bpf/libbpf_internal.h | |
parent | bad2e478af3b4df9fd84b4db7779ea91bd618c16 (diff) |
libbpf: Streamline error reporting for low-level APIs
Ensure that low-level APIs behave uniformly across the libbpf as follows:
- in case of an error, errno is always set to the correct error code;
- when libbpf 1.0 mode is enabled with LIBBPF_STRICT_DIRECT_ERRS option to
libbpf_set_strict_mode(), return -Exxx error value directly, instead of -1;
- by default, until libbpf 1.0 is released, keep returning -1 directly.
More context, justification, and discussion can be found in "Libbpf: the road
to v1.0" document ([0]).
[0] https://docs.google.com/document/d/1UyjTZuPFWiPFyKk1tV5an11_iaRuec6U-ZESZ54nNTY
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210525035935.1461796-4-andrii@kernel.org
Diffstat (limited to 'tools/lib/bpf/libbpf_internal.h')
-rw-r--r-- | tools/lib/bpf/libbpf_internal.h | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_internal.h index e2db08573bf0..8d59683ab246 100644 --- a/tools/lib/bpf/libbpf_internal.h +++ b/tools/lib/bpf/libbpf_internal.h @@ -11,6 +11,9 @@ #include <stdlib.h> #include <limits.h> +#include <errno.h> +#include <linux/err.h> +#include "libbpf_legacy.h" /* make sure libbpf doesn't use kernel-only integer typedefs */ #pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64 @@ -436,4 +439,27 @@ int btf_type_visit_str_offs(struct btf_type *t, str_off_visit_fn visit, void *ct int btf_ext_visit_type_ids(struct btf_ext *btf_ext, type_id_visit_fn visit, void *ctx); int btf_ext_visit_str_offs(struct btf_ext *btf_ext, str_off_visit_fn visit, void *ctx); +extern enum libbpf_strict_mode libbpf_mode; + +/* handle direct returned errors */ +static inline int libbpf_err(int ret) +{ + if (ret < 0) + errno = -ret; + return ret; +} + +/* handle errno-based (e.g., syscall or libc) errors according to libbpf's + * strict mode settings + */ +static inline int libbpf_err_errno(int ret) +{ + if (libbpf_mode & LIBBPF_STRICT_DIRECT_ERRS) + /* errno is already assumed to be set on error */ + return ret < 0 ? -errno : ret; + + /* legacy: on error return -1 directly and don't touch errno */ + return ret; +} + #endif /* __LIBBPF_LIBBPF_INTERNAL_H */ |